The present invention is based in the field of device-to-device (D2D) communication. D2D is a radio standard in LTE (long term evolution) that enables direct communication between various mobile communications terminals while bypassing a base station and thus a corresponding radio network. In the LTE standard, these mobile communications terminals are also referred to as user equipment (UE) and the direct communication link between mobile communications terminals is referred to as a sidelink. The D2D communication is considered to be a means for simplifying peer-to-peer (P2P) services between mobile communications terminals, for simplifying infrastructure-free communication in emergency situations, and for improving the network capacity by transferring data traffic out of the radio communications network. WO 2012/082024 A1 describes an example of D2D communication of this type.
In the following, the present invention and the problem addressed thereby will be explained on the basis of D2D communication, although this does not limit the invention to this type of mobile communications terminals or to the LTE standard.
Owing to the increasing functionality of modern mobile communications terminals, it is becoming ever more important to test them. If a mobile communications terminal is tested in the actual mobile communications network, the conditions are often not reproducible since limiting conditions such as cell power, timing, capacity utilisation, etc., can change constantly. Therefore, testing equipment exists that is designed specifically for testing mobile communications terminals. These mobile communications terminals to be tested are also referred to generally as “device under test” or DUT for short. While current testing equipment can emulate the functionality of base stations, future testing equipment must also be able to test the D2D communications properties of mobile communications terminals.
While D2D represents communication between two mobile communications terminals, situations also occur during practical use where one mobile communications terminal is addressed by a plurality of mobile communications terminals via respective D2D communication links. In this case, the base station of the mobile communications network configures common transmission resources for all the transmitting mobile communications terminals, from which said terminals select individual transmission resources at random. In addition, the corresponding transmission resources are communicated to the receiving mobile communications terminal as a receipt resource. Since the transmission resources are selected at random by the individual mobile communications terminals in the time and frequency domains, the situation may occur where at least two transmitting mobile communications terminals each transmit the data to the receiving mobile communications terminal on the same transmission frequency and at the same time, i.e. in the same time slot. This, however, causes interferences in the transmitted data signals. In this scenario, the receiving mobile communications terminals also have to operate correctly, which has to be verified by appropriate test scenarios. It is thus necessary to also be able to properly test mobile communications terminals under test for the event that interfering radio transmissions occur.